RESUMO
The structure analysis of porcine hemoglobin alphabeta dimer and the calculation of solvent accessible surface of the amino acids showed the epsilon-amino groups of the lysine are suitable for modification by polyethylene glycol (PEG). The modification of the lysine residues will not affect the carring oxygen capacity of Hb. Three types of linker have been designed to connect PEG and porcine hemoglobin. The lysines between porcine and bovine hemoglobin (pHb and bHb) are highly conserved, but the solvent accessible surface of conserved lysines are different. These suggested that the properties of homologous proteins are similar in pHb and bHb, but the characteristic derived from the homology analysis will be deviated from the actual status. The results of molecular dynamics simulation suggested that the chemical modified porcine hemoglobin would be no immunogenicity.